Proton-gated sodium channel impairing toxin

Channel Acid-sensing ion channels (ASICs) are voltage-insensitive, proton-gated cation channels activated by extracellular acidosis. In mammals, 4 genes encode at least 6 different subunits, the variants ASIC1a and ASIC1b, the variants ASIC2a and ASIC2b, and ASIC3 and ASIC4. Three identical or different subunits are required to form a functional channel (except for ASIC2b and ASIC4, which do not form proton-gated channels when expressed alone). Acid-sensing ion channel 1a (ASIC1a) and ASIC2 (both variants a and b) are widely expressed in neurons of the central nervous system, whereas almost all subunits (except ASIC4) are present in sensory neurons of the peripheral nervous system including nociceptors.
Toxin
Channel Toxins from different taxa that target channels.
Click on image to retrieve toxins of interest.
Human Snake Scorpion Cone
snail 		Spider Cnidarian Insect Other All
Subunit contained in homo- or heterotrimer:
ASIC1a image image - image image image - - image
ASIC1b image image - image image image - - image
ASIC2a image image - image image - - - image
ASIC2b image image - image image image - - image
ASIC3 image image - image - image - - image
ASIC4 image - - - - - - - -
all image image - image image image image - image
Link Back to Pharmacological target
Back to Ion channel impairing toxin
Nomenclature Toxins that target this type of receptor should be named π-toxins (pi in lower case) (see King et al., 2008)
Venom protein the most studied Psalmotoxin-1 (PcTx1)
Reference Baron et al, 2013
Cristofori-Armstrong and Rash, 2017

Venom protein entries in UniProtKB/Swiss-Prot

(all links/actions below point to uniprot.org website)

25 entries grouped by family

3 entries

FARP (FMRFamide related peptide) family

Select_allDeselect_all
CRF1_CONCF Conorfamide-As1 (Conorfamide-As1a) (CNF-As1a) ... Conus cancellatus (Cancellate cone) (Conus ...
CRF2_CONCF Conorfamide-As2 (Conorfamide-As2a) (CNF-As2a) ... Conus cancellatus (Cancellate cone) (Conus ...
FLP12_SPHAA FMRFamide-like peptide Sa12b (Sa-12) (Sa12b) ... Sphex argentatus argentatus (Black digger wasp)

2 entries

Not in a family

Select_allDeselect_all
ACTX1_ANTCS Acatoxin 1 (Acatx1) Anthopleura cascaia (Sea anemone)

pdb 6NK9

TXPM1_PHYCF Pi-phymatoxin-Pcf1a (Pi-PMTX-Pcf1a) ... Phymanthus crucifer (Red beaded anemone)

1 entry

NPY family

COS_CONTE Conorfamide Tx1.3 (AIVGRPRFamide) (AIVGRPRFa) ... Conus textile (Cloth-of-gold cone)

1 entry

Phospholipase A2 family, Group I subfamily, K49 sub-subfamily

"Phospholipase A2 family" VenomZone page
PA2HB_MICTN Basic phospholipase A2 homolog MitTx-beta ... Micrurus tener tener (Texas coral snake)

pdb 4NTW; 4NTX; 4NTY

2 entries

Psalmotoxin-1 family

Select_allDeselect_all
TX3A_HETMC Pi-theraphotoxin-Hm3a (Pi-TRTX-Hm3a) Heteroscodra maculata (Togo starburst tarantula) ...
TXP1_PSACA Psalmotoxin-1 (PcTx1) (Pi-theraphotoxin-Pc1a) ... Psalmopoeus cambridgei (Trinidad chevron ...

pdb 1LMM; 2KNI; 3S3X; 4FZ0; 4FZ1

4 entries

Psalmotoxin-1 family, Double-knot toxin subfamily

Select_allDeselect_all
TP1A_HADIN Pi-hexatoxin-Hi1a (Pi-HXTX-Hi1a) (Double-knot ... Hadronyche infensa (Fraser island funnel-web ...

pdb 2N8F

TP1B_HADIN Pi-hexatoxin-Hi1b (Pi-HXTX-Hi1b) (Double-knot ... Hadronyche infensa (Fraser island funnel-web ...
TP1C_HADIN Pi-hexatoxin-Hi1c (Pi-HXTX-Hi1c) (Double-knot ... Hadronyche infensa (Fraser island funnel-web ...
TP1D_HADIN Pi-hexatoxin-Hi1d (Pi-HXTX-Hi1d) (Double-knot ... Hadronyche infensa (Fraser island funnel-web ...

1 entry

Sea anemone structural class 9a family

TX9A_URTGR Precursor protein UG [Cleaved into: ... Urticina grebelnyi (Painted anemone)

pdb 2LZO

7 entries

Sea anemone type 3 (BDS) potassium channel toxin family

Select_allDeselect_all
5API_HETMG Pi-stichotoxin-Hmg5a (Pi-SHTX-Hmg5a) (Pi-AnmTX ... Heteractis magnifica (Magnificent sea anemone) ...
5BPIA_HETMG Pi/alpha-stichotoxin-Hmg5b (Pi/Alpha-SHTX-Hmg5b) ... Heteractis magnifica (Magnificent sea anemone) ...
BDS2_ANTEL Pi-actitoxin-Ael2b (Pi-AITX-Ael2b) (Toxin ... Anthopleura elegantissima (Green aggregating ...

pdb 1WXN; 2MUB

BDS5A_RADCR Pi-stichotoxin-Hcr5a (Pi-SHTX-Hcr5a) (APETx-like ... Radianthus crispa (Leathery sea anemone) ...
BDS5B_RADCR Pi-stichotoxin-Hcr5b (Pi-SHTX-Hcr5b) (APETx-like ... Radianthus crispa (Leathery sea anemone) ...
BDS5C_RADCR Pi-stichotoxin-Hcr5c (Pi-SHTX-Hcr5c) (APETx-like ... Radianthus crispa (Leathery sea anemone) ...
BDS5D_RADCR Pi-stichotoxin-Hcr5d (Pi-SHTX-Hcr5d) (APETx-like ... Radianthus crispa (Leathery sea anemone) ...

3 entries

Snake three-finger toxin family, Short-chain subfamily, Mambalgin sub-subfamily

Select_allDeselect_all "Snake three-finger toxin family" VenomZone page
3SX1_DENPO Mambalgin-1 (Mamb-1) (Pi-Dp1) Dendroaspis polylepis polylepis (Black mamba)

pdb 2MJY; 5DO6; 5DU1; 5DZ5; 7CFT

3SX2_DENPO Mambalgin-2 (Ma-2) (Mamb-2) (Pi-Dp2) Dendroaspis polylepis polylepis (Black mamba)

pdb 2MFA

3SX3_DENAN Mambalgin-3 (Mamb-3) Dendroaspis angusticeps (Eastern green mamba) ...

1 entry

Venom Kunitz-type family

"Venom Kunitz-type family" VenomZone page
VKTA_MICTN Kunitz-type neurotoxin MitTx-alpha Micrurus tener tener (Texas coral snake)

pdb 4NTW; 4NTX; 4NTY